Heavy duty trailers, such as those used by the military, have folding jack stands in the form of steerable landing legs for supporting the tongue of the trailer when not connected to the transport vehicle. In one such typical application, the M-149 Water Buffalo, a release handle with lock pins depending downwardly therefrom engage openings in the trailer to lock the landing leg in a raised position for towing by the transport vehicle. When the trailer is to be disconnected from the transport vehicle, the release handle is pulled upwardly to disengage the lock pins from the openings, allowing the landing leg to pivot downwardly to a vertical lowered position. The springs biasing the release handle are very strong requiring considerable strength for maintaining retraction thereby rendering the operating hand of limited assistance in retarding downward pivoting of the landing leg.
Inasmuch as it is not desirable to allow the landing leg to pivot downwardly freely, which could result in serious injury to legs and feet of the operator, a lower handle is provided on the foot of the landing leg for assisting the raising and lowering using the other hand of the operator. Single handed control, however, requires considerable strength and dexterity, even for the physically fit military personnel. Accordingly, injuries persist attributable to the lack of control in operating the landing feet on heavy vehicles. To overcome such hazards, generally two personnel are assigned to the task.
The military has sought to provide equipment that can be operated by a broad cross section of personnel. Preferably, the tasks could be performed by personnel in the 5th to 95th percentile. Current jack stands and landing legs designs cannot be operated this personnel range.